Standard library · Encoding and data

encoding/query

Reading and building the query string of a web address, such as q=hello&page=2.

import encoding.query

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Types
Functions

The query string is the part after the ? in a web address. One key may appear several times, as in tag=a&tag=b, so a QueryMap keeps a list of values for each key, and keeps the keys in order.

Functions such as Get and Has work on the string directly, which suits reading something once.

Types

`QueryOptions`

struct QueryOptions

The encoding options.

Name	Type	Description
`space_as_plus`	`bool = true`	Write a space as `+`; true by default. When false, `%20` is written.

encoding-query-Query.salam

import encoding.query

func main:
    text := "q=hello&page=2&tag=a&tag=b&empty="
    println query.Get(text, "q"), query.Get(text, "page"), query.Has(text, "empty"), query.Has(text, "x")
    println query.GetAll(text, "tag")
    mut m := query.Decode(text)
    println query.Size(m), query.Keys(m)
    query.Add(m, "tag", "c")
    query.Set(m, "page", "3")
    println query.Remove(m, "empty")
    println query.Encode(m)
    mut keep := Vector {} as Vector<str>
    keep.push("q")
    query.Retain(m, keep)
    println query.Encode(m)
    opts := query.QueryOptions {}
    println query.EncodeWith(query.DecodeWith("b=2&a=1", opts), opts)
    empty := query.NewQueryMap()
    println query.Size(empty)
end

Outputhello 2 true false ["a", "b"] 4 ["q", "page", "tag", "empty"] true q=hello&page=3&tag=a&tag=b&tag=c q=hello b=2&a=1 0

`QueryValues`

struct QueryValues

The values of one key.

Name	Type	Description
`items`	`Vector`	The values, in order.

The example for this item is shown with the ones above: encoding-query-Query.salam

`QueryMap`

struct QueryMap

A map from key to values that keeps the key order.

Name	Type	Description
`data`	`HashMap`	The values of each key.
`order`	`Vector`	The keys in the order they first appeared.

The example for this item is shown with the ones above: encoding-query-Query.salam

Functions

`NewQueryMap`

func NewQueryMap(): QueryMap

An empty map.

The example for this item is shown with the ones above: encoding-query-Query.salam

`DecodeWith`

func DecodeWith(qs: str, opts: QueryOptions): QueryMap

Reads a query string with the given options.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Decode`

func Decode(qs: str): QueryMap

Reads a query string; percent encoding and + are undone.

The example for this item is shown with the ones above: encoding-query-Query.salam

`EncodeWith`

func EncodeWith(values: QueryMap, opts: QueryOptions): str

Turns a map into a string with the given options.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Encode`

func Encode(values: QueryMap): str

Turns a map into a query string.

The example for this item is shown with the ones above: encoding-query-Query.salam

`GetAll`

func GetAll(qs: str, key: str): Vector<str>

Every value of a key in the string.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Get`

func Get(qs: str, key: str): str

The first value of a key in the string, or an empty string when it is absent.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Has`

func Has(qs: str, key: str): bool

True when the key is in the string, even with an empty value.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Size`

func Size(m: QueryMap): int

The number of keys.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Add`

func Add(values &: QueryMap, key: str, val: str)

Adds another value to a key, keeping the earlier ones.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Set`

func Set(values &: QueryMap, key: str, val: str)

Replaces every value of a key with one value.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Keys`

func Keys(values: QueryMap): Vector<str>

The keys, in order.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Remove`

func Remove(values &: QueryMap, key: str): bool

Removes a key and its values and says whether it was there.

The example for this item is shown with the ones above: encoding-query-Query.salam

`Retain`

func Retain(values &: QueryMap, keep: Vector<str>)

Keeps only the keys you name.

The example for this item is shown with the ones above: encoding-query-Query.salam